"Subscribe Pending" on some communities of an instance, but not others

I have an account on Lemmy.world and I have successfully subscribed to some communities on other instances such as lemmy.ml and beehaw.org. I can see the status of everything on https://lemmy.world/communities/listing_type/Subscribed/page/1

But some of my subscription requests to communities on those instances show "Subscribe Pending". Does each community on an instance need to give permission for me to join? Just as an example, Technology@beehaw.org and Science@beehaw.org are pending, along with Reddit@lemmy.ml and Technology@lemmy.ml. Also, all of my requests to kbin.social are pending, such as RedditMigration@kbin.social.